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93 V8 Swap Into 90 4 Cyl. Wiring Harness Help

  • Thread starter Thread starter CobraWannabe
  • Start date Start date Feb 25, 2014

CobraWannabe

Member
Jul 16, 2003
321
0
17
Lancaster, PA
Feb 25, 2014
#1
  • Feb 25, 2014
  • #1
First, thanks to Jrichker for all of his help so far. I'm starting this thread in continuation to the "fuel pump not turning on" thread, hoping to find an answer.

The short version.
I have a 1990 coupe that used to be 4 cyl. and now has a 93 Cobra engine swapped in. Anyone who may have an answer to my problem probably already knows the engine wiring harness needs to match the rest of the car's harness (inside the car). So this is where I'm at. When my brother did the swap, the car ran the way it is (for a while) And now the fuel pump doesn't turn on. So will these harnesses still work together if I can chase down the problem? Or could the differences be what caused the failure? The engine compartment fuel pump relay works and sends power out, but then there's no power at the fuel inertia switch. I'm starting to wonder if the "other" fuel pump relay (under the driver's seat) is bad. Plus who wants 2 fuel pump relays when there's no need for it? I don't know. I'm just trying to see what my options are since a 93 harness for the interior is about $200.

Also, If I find a 93 wiring harness from a hatch, is it going to work in my coupe? (That's the reason he didn't use it in the first place, and now it's gone.)
 

CobraWannabe

Member
Jul 16, 2003
321
0
17
Lancaster, PA
Feb 26, 2014
#2
  • Feb 26, 2014
  • #2
TTT.

I'm also reading that the wrong O2 harness could do damage. Is the O2 harness a seperate harness from the others?
 
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